“There aren’t words to describe the sadness I feel about the accident that took the life of Kevin Ward Jr.,” Stewart said in a statement released Sunday. “My thoughts and prayers are with his family, friends and everyone affected by this tragedy.”

“We feel strongly that this is the right thing to do,” Zipadelli said, calling Ward Jr.’s death “an unbelieveable tragedy.”

“He’s going through a tough time,” Zipadelli said of Stewart. “It’s emotional for him. We as a group support him. We feel like he’s doing the right thing.”

NASCAR supported Stewart’s decision and said that it would monitor the situation as the investigation continues. In a statement, NASCAR said that the organization’s “thoughts and prayers go out to the family, friends and fellow competitors of Kevin Ward Jr.”